Air cleaner



Q 1925' F. A. DONALDSON AIR CLEANER Filed Nov. 12, 1921 Patented Oct. 13, 1925.

FRANK A. DONALD'SON OF ST. PAUL, MINNESOTA.

AIR CLEANER.

Application filed November 12, 1921. "Serial 110315628.

To all whom it may concern:

Be it lmown that I, FRANK A. DONALDSON, a citizen of the United States, residing at St. Paul, in the county of Ramsey and State of Minnesota, have invented certain new and useful Improvements in Air Cleaners; and I do hereby declare the following to be a full, clear, and exact description ofthe invention, such as'will enable others skilled in the art to which it appertains to make and use the'same.

M present invention relates to air cleaners or use in connection with the carbureters of internal combustion engines and is in the nature of a modification ofor improvement on the air cleaner disclosed and broadly claimed in my Patent #1,405,399.

Generally stated, the invention consists of the novel construction, arrangement and combinations of parts hereinafter described and defined in the claims.

The present invention, in common with the invention of my prior application, employs a centrifugal or so-called cyclone actmg dust collector for primarily removing most of the dust from the air.

The present invention, however, simplifies somewhat the construction illustrated 1n the drawings of my prior application and provides certain novel and lmpo'rtant distinctive features of improvement as will hereinafter more fully appear.

In the accompanying drawings, which illustratethe invention, like characters indi cate like arts throughout the several views.

Referring to the drawings:

Fig. 1 shows the cleaner chieflyin vertical section but with some partsin full; and

Fig. 2 is a perspective of the filter-containing member removed from the casing.

The casing of the cleaner is made up of a lower truncated conical lower section or shell 32 provided at its bottom with a de tachable dust-collecting jar 33 and baflie plate 34, which may be of any suitable form but which, as shown, is substantially pyramidal in shape and is connected to thecasing 32 at four corners and in a manner that leaves dust passages adjacent to the shell. The shell 32 has an annular to plate 36 formed with a threaded neck 3 adapting it to be screwed into a threaded portion of an upper case section 38, which latter, as shown, has a lateral air outtake tube or passage 39. In this arrangement, a filter 40 preferably a compact body of hair, is placed /of which afi'ords a collar and the depending portion of which 'afiords an annular air distributor or ski-rt. This tube 41 is removable with the filter when the lower case section 32 is unscrewed from the upper case section 38; and, to support said tube and filter in working position, said tube is provided with an upstanding sleeve 42 that is adapted'to in a large air tube 41, the upper portion rest loosely upon the upper end of. the

threaded neck 37. The jar or dust receptacle 33'is made readily removable from the bottom of the shell 32 and this, as shown, is afforded by coarse threaded engagement.

The shell 32,, above the bottom of the skirt portion of the tube 4.1, is provided with tangential air intake ports 35, preferably formed bypartly severed inwardly pressed lips that cause the inwardl drawn dustladen air to take up a whirlmg motion immediately around said skirt. T us, the dustladen air is immediately caused to whirl, so that the dust will be thrown by centrifugal force against the walls of the shell 32 and will be. given a whirling motion toward and finally to the bottom of the shell and from thence into the dust receptacle 33.' The air from which the greater part of the dust has been precipitated will be' drawn upward through the air tube 41 and the remaining dust will be removed therefrom by the filter 4.0, so that only very clean air will reach the upper air chamber or compartment formed within the upper case section or shell 38.

g This filter, the preferred form of which is here illustrated, while of very simple construction and'of low manufacturing cost, has, in practice, been found highly efiicient as a dust collector and air cleaner for use in connection with internal combustion engines. Of course, in practice, the air outlet tube 39 will be connected to the carbureter of such engine so that only clean air will be de livered to the carbureter and from thence to the engine cylinders.

What I claim is:

- 1.'A combined gravity and filter-operating dust collector comprising a casing provided at its upper portion with circumferentially spaced air intake passages and provided at its bottom with a dust receptacle, an upper shell to which said casin is detachably secured and from which it epends, and a filter-eqhuipped tube of considerably less diamete t an the upper portion of said casing, applied through the top of said casing and extended within said casing to a plane below the air intake passages thereof.

2. A combined gravity and filter-operating dust collector comprising an inverted truncated conical casing having circumferentially spaced tangential air intake passages near its top and rovided with an upstanding threaded nec of less diameter than its 10 top portion, an upper shell having a threaded portion into WhlCh the threaded sleeve of said casing is screwed, a dust receptacle detachably applied to the contracted lower end of said casing, an air tube detachably applied in the threaded neck of said casing and extended within said casing to a plane below said air intake passages, and a body of filtering material in said air tube, removable therewith from said casing when said casing is detached from said upper shell.

In testimony whereof I afiix my signature.

FRANK A. DONALDSON. 

